A Use-After-Free vulnerability in the Layer 2 Address Learning Daemon (l2ald) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker to cause l2ald to crash leading to a Denial-of-Service (DoS). In an EVPN-VXLAN scenario, when state updates are received and processed by the affected system, the correct order of some processing steps is not ensured, which can lead to an l2ald crash and restart. Whether the crash occurs depends on system internal timing which is outside the attackers control. This issue affects: Junos OS: * All versions before 20.4R3-S8, * 21.2 versions before 21.2R3-S6, * 21.3 versions before 21.3R3-S5, * 21.4 versions before 21.4R3-S4, * 22.1 versions before 22.1R3-S3, * 22.2 versions before 22.2R3-S1, *
The following software releases have been updated to resolve this specific issue: Junos OS: 20.4R3-S8, 21.2R3-S6, 21.3R3-S5, 21.4R3-S4, 21.4R3-S5, 22.1R3-S3, 22.2R3-S1, 22.3R3, 22.3R3-S2, 22.4R2, 23.2R1, and all subsequent releases; Junos OS Evolved: 20.4R3-S8-EVO, 21.2R3-S6-EVO, 21.3R3-S5-EVO, 21.4R3-S4-EVO, 22.1R3-S3-EVO, 22.2R3-S1-EVO, 22.3R3-EVO, 22.4R2-EVO, 23.2R1-EVO, and all subsequent releases.
There are no known workarounds for this issue.
| Product | Vulnerable range | Fixed version | Advisory |
|---|---|---|---|
| Juniper Networks Junos OS | <20.4R3-S8 | 20.4R3-S8 | advisory ↗ |
| Juniper Networks Junos OS | >=21.2<21.2R3-S6 | 21.2R3-S6 | advisory ↗ |
| Juniper Networks Junos OS | >=21.3<21.3R3-S5 | 21.3R3-S5 | advisory ↗ |
| Juniper Networks Junos OS | >=21.4<21.4R3-S4 | 21.4R3-S4 | advisory ↗ |
| Juniper Networks Junos OS | >=22.1<22.1R3-S3 | 22.1R3-S3 | advisory ↗ |
| Juniper Networks Junos OS | >=22.2<22.2R3-S1 | 22.2R3-S1 | advisory ↗ |
| Juniper Networks Junos OS | >=22.3<22.3R3 | 22.3R3 | advisory ↗ |
| Juniper Networks Junos OS | >=22.4<22.4R2 | 22.4R2 | advisory ↗ |
| Juniper Networks Junos OS Evolved | <20.4R3-S8-EVO | 20.4R3-S8-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=21.2-EVO<21.2R3-S6-EVO | 21.2R3-S6-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=21.3-EVO<21.3R3-S5-EVO | 21.3R3-S5-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=21.4-EVO<21.4R3-S4-EVO | 21.4R3-S4-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=22.1-EVO<22.1R3-S3-EVO | 22.1R3-S3-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=22.2-EVO<22.2R3-S1-EVO | 22.2R3-S1-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=22.3-EVO<22.3R3-EVO | 22.3R3-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=22.4-EVO<22.4R2-EVO | 22.4R2-EVO | advisory ↗ |